CSA Catapult shows high-performing GaN PA
High linearity amplifier targets next generation satellite communications
A high-performing GaN power amplifier for use in satellite communication applications has been developed by a team of engineers at the Compound Semiconductor Applications (CSA) Catapult and Cardiff University in the UK. The GaN device operates in the 26-31GHz band with an output power greater than 6 watts.
Presenting its results at the European Space Agency’s ‘1st Space Microwave Week’ conference, the team says the GaN power amplifier has performed extremely well on linearity tests developed by CSA Catapult to help test the technology before it makes its way into real world-applications.
When designing satellite communication systems, linearity (the accuracy of reproducing the input signal that the amplifier is boosting) is key. It preserves the information content and quality of the signal and reduces the interference with other signals in the same frequency band. The need to test the linearity with real data signals, led CSA Catapult and Cardiff University engineers to develop a new testbed that can carry out these measurements automatically.
Ehsan Azad, an RF engineer at CSA Catapult who led the research and presented it at the ESA conference said: “With the increasing demand for high-speed and reliable communication, satellite communication systems are becoming more advanced and sophisticated. As these systems continuously evolve through increased bandwidths and more complex signals being transmitted, it becomes more challenging to maintain linearity specifications whilst continuing to focus on efficiency improvements.
“As we move toward the more energy-efficient power amplifier architectures, alongside the use of relatively new GaN technology, a lot of the assumptions made on power amplifier linearity are being invalidated. Similarly, there are still concerns about the linearity of the GaN-based power amplifier.
“That is why it is critically important that state-of-the-art tests such as ours are developed to determine the suitably of compound semiconductor materials for building the next generation of satellite communication applications.”